Commander Sinclair is the first commander of Babylon 5 and a representative of the Earth Alliance. He became commander after the Minbari refused to accept a number of higher ranked officers as the commander of B5. He is a fighter pilot and a survivor of the Battle of the Line during the Earth-Minbari war. He was born on Mars Colony. After President Santiago is assassinated he is reassigned as the ambassador to Minbar. There he becomes Ranger one. He eventually goes back in time a thousand years with Babylon 4 and becomes Valen a Minbari not of Minbar.